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Subject: Re: O_DIRECT fails in some kernel and FS
To: lord@sgi.com (Steve Lord)
Date: Mon, 4 Feb 2002 15:46:20 +0000 (GMT)
Cc: cw@f00f.org (Chris Wedgwood), garzik@havoc.gtf.org (Jeff Garzik),
        mason@suse.com (Chris Mason), andrea@suse.de (Andrea Arcangeli),
        akpm@zip.com.au (Andrew Morton), gallir@uib.es (Ricardo Galli),
        linux-kernel@vger.kernel.org (Linux Kernel)
In-Reply-To: <1012835730.26397.519.camel@jen.americas.sgi.com> from "Steve Lord" at Feb 04, 2002 09:15:30 AM
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From: Alan Cox <alan@lxorguk.ukuu.org.uk>
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> If an application is multithreaded and is doing mmap and direct I/O
> from different threads without doing its own synchronization, then it
> is broken, there is no ordering guarantee provided by the kernel as
> to what happens first.

Providing we don't allow asynchronous I/O with O_DIRECT once asynchronous
I/O is merged.

Alan
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